1. Field of the Invention
The present invention relates to a high bulk laminated board, particularly but not exclusively to a high bulk laminated board for use in the production of large displays, show-cards, graphic panels and the like. The present invention also relates to an apparatus for producing high bulk laminated board and a method relating thereto.
2. Description of Related Art
Foam centred board (“Foam Board”) is commonly used for the production of large displays, show-cards, graphic panels, and the like, where high rigidity, thickness and low weight, combined with high quality printable facings are required.
The most commonly used thicknesses of Foam Board are 3 and 5 mm. Foam Board typically comprises a core of expanded polystyrene or polyurethane foam, lined both sides with graphic board such as coated solid bleached sulphate board (SBS) or coated folding boxboard (GC2).
There are major environmental disadvantages in using foam board as follows:    1) It is impossible to recycle, being a composite of plastic foam centre and cellulose based liners.    2) The plastic foam centre is produced from petrochemicals which are a finite resource.    3) The only methods of disposal are:            i) landfill, which is burying problems for future generations; and        ii) incineration, which generates carbon dioxide and, if not carried out expertly, hazardous chemical compounds.        
There is a growing demand for an environmentally benign alternative based on 100% cellulose fibre which can be recycled.
One type of board which has been considered as an alternative to Foam Board is corrugated board, typically in the form of double faced B, C and E or double wall EB, EE and NE flute constructions.
However, corrugated board is not able to fulfil all the criteria for use in large displays, show-cards, graphic panels, and the like as it has the following disadvantages:    1) It is prone to bowing because of moisture imbalance caused by the method of production resulting from the lamination of the face liners at different points under differing pressures.    2) The flutes tend to show through the face liners so causing flute shadow when printed.    3) In order to provide a smoother printing surface with less flute shadow, composite constructions such as EB or NE are made with one side having a much finer flute profile. This is an imbalanced construction which is liable to bow.    4) There is a tendency for more bruising and wash boarding of the face liner to show on one side of the board which detracts from the image when it has to be printed both sides.    5) Corrugated board is much less rigid in the cross flute direction and is more prone to folding along the flutes.    6) It is difficult to produce constructions with creases along the flutes as the board tends to roll either side of the crease line.    7) Corrugated board has a high moisture level when first produced and this can lead to bowing.    8) The choice of face liners is restricted to those that will withstand the high temperatures and pressures used in the manufacture of the board.
It is also known that globular (cup-and-ball) embossed paper is used to produce a multi-ply paper construction for use in the confectionery market commonly known as Cushion Pad. As the name suggests the product is designed to be extremely light and compressible. Typically the grammage of papers used is less than 50 gsm with the total construction weight of a 5 ply being less than 200 gsm. This product has no rigidity.
The method of production is not controlled so that the embossed patterns of the plies are not registered to each other and a 5 ply construction has to have an intermediate ply of un-embossed paper.
An aim of the present invention is to address the problems that the prior art has described herein or elsewhere.